Key findings on large branchiopods from the threatened Bardača Wetland Ramsar site and surrounding areas in Bosnia and Herzegovina

Abstract

Studies on large branchiopods, crustaceans that inhabit temporary waters in Bosnia and Herzegovina, are relatively rare. Recently published data from the Ramsar site “Bardača Wetland” and the neighboring area of Donja Dolina revealed the presence of nine species. The nine-year study included the investigation of environmental gradients in regularly flooded and non-flooded areas where species occur, including 28 ephemeral sites. The ordination of environmental factors, species and samples on the space defining the first two CCA axes, as well as post-hoc test analyses, confirmed a significant influence of inundation. Conductivity, temperature and oxygen are the most important factors for species distribution. The temperature and oxygen values were independent of each other in the ordination. The position of species on the CCA axes revealed different patterns and in some cases was dominated by a single variable—conductivity (e.g. Lepidurus apus, and Cyzicus sp.), while most of branchiopod taxa occupied a lower portion in the ordination. Cluster analysis of the different taxa and localities revealed a complex pattern. In most cases, there was no clear subdivision between sites and species in terms of flooding. However, some species were clearly dependent on rainfall and groundwater (Eubranchipus. (S.) grubii, Linderiella sp. and Triops cancriformis), others exclusively on flood waters (L. apus).